Elastin Microfibril Interface Located Protein 1 (EMILIN1) is a glycoprotein that plays an important role in the extracellular matrix (ECM). It is widely present in the extracellular matrix of arteries, lymphatic vessels and other tissues. EMILIN1 plays an important role in several biological processes, such as participating in the biosynthesis of elastic fibers (elastogenesis), maintaining vascular cell morphology and regulating cell signaling. Besides, Integrin Beta 1 (ITGb1) has been identified as an interactor of EMILIN1, thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human EMILIN1 and recombinant human ITGb1. Briefly, EMILIN1 was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to ITGb1-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-EMILIN1 pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody for 1h at 37℃, wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50 µL stop solution to the wells and read at 450/630 nm immediately. The binding activity of recombinant human EMILIN1 and recombinant human ITGb1 was shown in Figure 1, the EC50 for this effect is 6.64 ug/mL.